A microscopic image as it appears in Image Annotation Tool (IAT). This image is from the histology atlas by Letty Moss-Salentijn, et al. Labels have been prepared in IAT by the instructor. Students can keep them visible or hidden if they wish to test themselves. Students are able to use the tools in the lower right corner to write in a separate layer their own labels and annotations and share them with the instructor and with each other.

A picture is worth a thousand words, but what is the value of a thousand pictures, or ten thousand? Very valuable indeed, says Letty Moss-Salentijn, D.D.S., Ph.D., senior associate dean in the School of Dental and Oral Surgery, who has worked with Columbia's Center for New Media Teaching and Learning to develop a powerful new image-based teaching tool that she expects will greatly assist students in understanding oral histology.

After more than 30 years of teaching oral histology, Dr. Moss-Salentijn knows there's no such thing as too many images when it comes to helping students study tissue structure. She has always been a pioneer in disseminating images to students  early in her career, she co-authored one of oral histology's seminal atlases, still in use today. Now, The Image Annotation Tool (IAT) she has helped develop disseminates more images more effectively than ever. The IAT makes it possible to store, classify, annotate, and share a theoretically limitless number of images in a Web-based environment. IAT improves upon traditional teaching devices  the microscope and histological atlases  while also addressing a generational shift: students who are more comfortable with digital images than with slides at a microscope.

Broadening Exposure

In traditional histology, students are able to use the microscope to explore the many aspects of tissues. Most however, are exposed to a limited range of images they are able to view by using microscopes and histological atlases. Such relatively narrow exposure means that students develop a fixed idea of how a particular tissue looks and are frequently unable to extrapolate their understanding when presented with new images that vary even a little from what they have seen before. Traditional microscopy also poses another problem  often the students who enter Dr. Moss-Salentijn's lab have not even used microscopes before. "This is a very sad reality," she says, "But most students now come to medical and dental schools without a clue how to use an instrument that has been basic to science for hundreds of years."

It is a problem that might make some professors tear their hair and rant against the lapses of contemporary education, but Dr. Moss-Salentijn has taken a more level-headed and pragmatic approach. "I love microscopes," she says, "but do students really need to have that skill in the future? What they need to know is how to look at an image and recognize it. What they need to get out of this is the ability to interpret what they see."

So, Dr. Moss-Salentijn set out to develop a new way of teaching that would be more effective for a new generation of students. After a few small-scale experiments in her own classroom, where she allowed students to use either traditional microscopy or a limitless number of digital images they could glean from the Internet, she determined that digital images were at least  if not more  effective as teaching tools than conventional tissue slides. Thus prepared, she collaborated with Columbia's Center for New Media Teaching and Learning (CNMTL) to develop the customized web-based IAT, which was rolled out last year.

Once the bugs were worked out, Dr. Moss-Salentijn and CNMTL had created a tool that would not only allow students exposure to many more images  in addition to the images the professor uploads, students can share their own, or even link to external urls  it also would encourage more active and interactive learning. "The students truly enjoy putting the labels on," says Dr. Moss-Salentijn.

Unlike other electronic annotation tools, the IAT can save image annotations from different users and enables interactive learning even outside of class. The tool has been a hit. During the first semester it was used, Dr. Moss-Salentijn found that even as she was putting slides on, her students were accessing and annotating them. "As I was uploading slides, I saw the slides jumping around [on the index]. I realized that students were using them literally as I uploaded them," she says.

The ability of individual users to annotate the images and share them among classes has broad applicability beyond histology, and even medical classes. In addition to Dr. Moss-Salentijn's histology courses, a Barnard English professor has used IAT to annotate images of original texts. Michelle Hall, educational technologist and IAT project manager at CNMTL, sees this as just the beginning. "We're really thinking about how others can use this tool," she says. She envisions extending its use to art history, archeology and other disciplines that rely heavily on imagery.

"We are now compiling cases to determine how other disciplines are using digital images at Columbia, and how the IAT can be used in these new contexts," says Ms. Hall. "Next year should be a big year for the IAT and we should see a lot of cool things come of it."